The role of genetic factors in drug addiction vulnerability is supported by twin and adoption studies. In September 1998, NIDA issued a Request For Applications (RFA), entitled, "Genetics of Drug Addiction Vulnerability, " (RFA DA-99-003) to identify chromosomal regions harboring genes that confer susceptibility to these disorders, as a crucial first step in the effort to positionally clone precise genes. Applicants were requested to provide clinical, diagnostic, pedigree structure information, and to create cell lines from blood samples collected in projects funded under this RFA over the next five years. The objective of this contract is to establish a center to receive data and blood samples from projects funded under RFA DA-99-003 and other grants supporting research on the genetics of addiction vulnerability, in order to reduce the cost to both NIDA and to the investigators. The NIDA Center for Genetic Studies will process these data and materials to create databases, cell lines, and DNA samples, and will widely distribute all data and materials in the NIDA Human Genetics Initiative to qualified investigators in the scientific community.